178 THE VITAL FUNCTIONS. 



§ 7. Receptacles for retaining Food. 



Provision is often made for the retention of the 

 undigested food in reservoirs, situated in different 

 parts of the mouth, or the oesophagus ; instead of 

 its being immediately introduced into the sto- 

 mach. These reservoirs are generally employed 

 for laying in stores of provisions for future 

 consumption. Many quadrupeds have cheek 

 pouches for this purpose : this is the case with 

 several species of Monkeys and Baboons ; and 

 also with the Mus cricetus, or Hamster. The 

 Mus bursarius, or Canada rat, has enormous 

 cheek pouches, which, when distended with food, 

 even exceed the bulk of the head. Small cheek 

 pouches exist in that singular animal, the Orni- 

 thorhyncJms. The Sciurus palmarmn, or Palm 

 squirrel, is also provided with a pouch for laying 

 in a store of provisions. A remarkable dilatation 

 in the lower part of the mouth and throat, 

 answering a similar purpose, takes place in the 

 Pelican; a bird which displays great dexterity 

 in tossing about the fish with which it has 

 loaded this bag, till it has brought it into the 

 proper position for being swallowed. The Whale 

 has also a receptacle of enormous size, extending 

 from the mouth to a considerable distance under 

 the trunk of the body. 



